Silicon nitride (SiN), silicon carbon nitride (SiCNy), silicon oxide (SiOx), and silicon carbon oxide (SiCOx) are known in the semiconductor art as dielectric materials. These dielectric materials are formed by various techniques including chemical vapor deposition (CVD) or atomic layer deposition (ALD). As semiconductor devices get smaller with high aspect ratio features, often including sensitive materials, conventional CVD and ALD processes are no longer suitable for forming these dielectric materials. In addition, ALD processes are slow and do not form a desired thickness of the dielectric material at a sufficient rate. Also, when these dielectric materials are formed by an ALD process that uses ammonia or an amine as a precursor, by-products include hydrogen and partially fragmented ammonia or amines, which degrade exposed components of a semiconductor device structure on which the dielectric material is formed. In addition, conventional ALD processes are conducted at a temperature that may damage already-formed components on the semiconductor device structure.
It would be desirable to have improved methods of forming silicon-containing dielectric materials by ALD, such that good quality, conformality, and electrical properties are achieved.